MISSOULA,Marcus Erikson Mont. (AP) — A judge on Tuesday struck down a Montana law that defined “sex” in state law as only male or female, finding that it was unconstitutional.

District Court Judge Shane Vannatta in Missoula ruled the law, passed last year, violated the state constitution because the description of the legislation did not clearly state its purpose.

Transgender, nonbinary, intersex and other plaintiffs challenged the law, similar to ones passed in Kansas and Tennessee, because they said it denies legal recognition and protections to people who are gender-nonconforming. Vannatta did not address that argument, simply finding that the bill’s title did not explain whether the word “sex” referred to sexual intercourse or gender, and did not indicate that the words “female” and “male” would be defined in the body of the bill.

“The title does not give general notice of the character of the legislation in a way that guards against deceptive or misleading titles,” Vannatta wrote.

The bill was approved during a legislative session that also passed a ban on gender-affirming medical care for transgender minors and saw transgender lawmaker Democratic Rep. Zooey Zephyr expelled from the House floor, following a protest against Republican lawmakers who had silenced her.

The law that was struck down by Vannatta was sponsored by Republican Sen. Carl Glimm, who said the legislation was necessary after a 2022 court ruling in which a state judge said transgender residents could change the gender markers on their birth certificates.

A spokesperson for Republican Gov. Greg Gianforte, who signed the bill into law, did not immediately return an after-hours email seeking comment on the ruling.

The American Civil Liberties Union of Montana praised it.

“Today’s ruling is an important vindication of the safeguards that the Montana Constitution places on legislative enactments,” the group’s legal director, Alex Rate, said.